iOS - Data corruption after downgrade

Question

Yesterday, I downgraded my iPhone 7 from iOS 11.3 Developer Beta 1 to iOS 11.2 Release (It was being signed then) using the "Upgrade" option. Downgrade went fine, but after the downgrade, the device started overheating and I discovered most of my data was corrupted, including Social media, Wifi and iCloud passwords and contents and some System Settings. I had no option but to restore the iPhone, so I restored to iOS 11.2 and it works fine now.

My question is: Is this a normal behavior after a downgrade (from a beta) using the "Update" option?

Answer 1

Apple say in all beta documentation that you can not downgrade from a beta to an earlier version. What they mean is that behavior is undefined, and that if you run into problems when you try this, then you are on your own as it is not an action that they support.